Two new fairy shrimp of the genus Streptocephalus (Branchiopoda: Anostraca) from North America

Abstract

Two new species of fairy shrimp from North America, Streptocephalus henridumontis and Streptocephalus thomasbowmani, are diagnosed and figured. A brief account on the conservation status of the New World species of the genus and an updated species identification key are included. Streptocephalus thomasbowmani n. sp., endemic to New Mexico, U.S.A., is morphologically similar to S. dorothae. Streptocephalus henridumontis n. sp., whose populations occur along the Sonoran desert in northwestern México and southwestern United States, is morphologically similar to S. mackini. The peduncle of the antennal distal outgrowth of the two new species is of the long type. Streptocephalus thomasbowmani has uniramous ovaries, whereas S. henridumontis has biramous ovaries. With the inclusion of the new taxa, the number of species of the genus recorded from the American continent is 15. Seven (S. dorothae, S. henridumontis, S. linderi, S. mackini, S. sealii, S. similis, and S. texanus) have a wide geographical distribution and seem to be under no immediate threat. Conversely, eight species have a restricted distribution. Thus, S. antillensis, S. kargesi, and S. potosinensis can be considered as Critically Endangered (CE), and S. thomasbowmani, S. guzmani, S. mattoxi, S. moorei, and S. woottoni as Endangered species (EN), following the IUCN red list criteria.